1. Field of the Invention
The present invention relates to a camera which loads a film cartridge capable of discriminatively indicating a use state of a film, i.e., an unused film, a partially-used film which is exposed up to an intermediate frame, and is rewound, or a used film which is rewound after all the frames are exposed, in accordance with the rotational angular position of a spool around which a film is wound.
2. Related Background Art
The present assignee previously proposed a camera which uses the above-mentioned film cartridge (Japanese Patent Application No. 2-189994).
This camera comprises a drive member (corresponding to a spool drive means; e.g., a rewinding fork), which can be engaged with the spool of the cartridge at only a predetermined angular position. The spool is rotated by the drive member to rewind a film, and thereafter, is further rotated to indicate the used state of the film (a used film or partially-used film). According to this camera, since an operator can confirm the use state of a film by observing the cartridge, he or she can be prevented from erroneously loading, e.g., a used cartridge in a camera again to perform a photographing operation.
However, the camera disclosed in Japanese Patent Application No. 2-189994 does not drive the drive member to an initial position after a film is rewound and a cartridge is unloaded, and this presents a problem in practice.
Almost all cartridges to be loaded in the camera store unused film (unused cartridges), as a matter of course. On the other hand, most cartridges when unloaded are used or partially-used cartridges, and such states are discriminatively indicated. Therefore, after these cartridges are unloaded, the drive member is located at a rotational position where it can be engaged with a used or partially-used cartridge, but is not located at a position where it can be engaged with an unused cartridge. For this reason, when a cartridge is unloaded, and an unused cartridge is loaded, the spool cannot often be easily engaged with the drive member of the camera, thus making a loading operation difficult.